Peruvian Journal of Agronomy http://revistas.lamolina.edu.pe/index.php/jpagronomy/index RESEARCH ARTICLE https://doi.org/10.21704/pja.v7i2.2053 Received for publication: 26 July 2023 Accepted for publication: 26 August 2023 Published: 31 August 2023 ISSN: 2616-4477 © The authors. Published by Universidad Nacional Agraria La Molina This is an open access article under the CC BY Possible induction of systemic resistance to Lasiodiplodia theobromae in avocado (Persea americana Mill.) under semi- controlled conditions at La Molina Posible inducción de resistencia sistémica a Lasiodiplodia theobromae en aguacate (Persea americana Mill.) en condiciones semicontroladas en La Molina Nery Veronica Jimenez-Ariza 1* ; Jose Miguel Soto-Heredia 2 ; Andrés Virgilio Casas-Díaz 3 ; Liliana María Aragón-Caballero 2 1 Universidad Nacional Agraria La Molina, Faculty of Agronomy, Av. La Molina S/N, Lima-Peru 2 Universidad Nacional Agraria La Molina, Faculty of Agronomy, Phytopathology department, Av. La Molina S/N, Lima-Peru. 3 Universidad Nacional Agraria La Molina, Faculty of Agronomy, Horticulture department, Av. La Molina S/N, Lima-Peru. *Corresponding author: 20150045@lamolina.edu.pe *https://orcid.org/0000-0002-3213-4340 Abstract The production and export of avocado fruits, cultivar Hass, has grown exponentially in recent years in Peru, however, a high incidence of symptoms such as regressive death, cankers on plant branches, and fruit rot have been observed afecting optimal crop production and fruit quality. These symptoms are mainly generated by Lasiodiplodia theobromae fungus, whose control is limited to a few active ingredients that tend to generate pathogen resistance. The present investigation had as objective to evaluate the inducing efect of resistance in the control of Lasiodiplodia theobromae in avocado (Persea americana) cultivar Hass of fve bioproducts: ProtecSea, Barrera, Timorex Gold, T 22, Vacun Q Pro and water as a control treatment, with a total of 6 treat- ments with 4 replications, 3 avocado trees per replication. One-year-old avocado trees cultivar Hass were used. Treatments were applied three times via drench at ten-day intervals. Five days after the last application L. theobromae was inoculated in the avocado trees cultivar ‘ Hass’ and 40 days after the inoculation, the pa- rameters were evaluated: length of the disease lesion, percentage of dry matter of the roots and leaves, and length of the roots. It was observed that treatments, with the exception of treatment T1 (Control), reduced the length of the disease lesion infected by L. theobromae inside the stem. Treatment T6 (T.22) resulted in a higher percentage of root dry matter (46.52 %) compared to the control treatment (41.21 %). On the other hand, there were no signifcant diferences in leaf dry matter content among treatments. Additionally, it was observed that treatment T2 (ProtecSea) reported a root length of 56.80 cm, followed by treatment T6 (T.22) with 54.90 cm. These results are important to continue with investigations into inducing systemic resistance in plants. Keywords: Lasiodiplodia theobromae, Persea americana, Barrera, Vacun Qpro, Timorex gold, Trichoderma harzianum, ProtecSea. Resumen La producción y exportación de frutos de palta, cultivar Hass, ha crecido exponencialmente en los últimos años en el Perú, sin embargo, se ha observado una alta incidencia de síntomas como muerte regresiva, cancros en ramas de la planta y pudrición del fruto que afectan la producción óptima del cultivo y la calidad del How to cite this article: Jimenez-Ariza, N., Soto-Heredia, J., Casas-Díaz, A., Aragón-Caballero, L. (2023). Possible induction of systemic resistance to Lasiodiplodia theobromae in avocado (Persea americana Mill.) under semi-controlled conditions at La Molina. Peruvian Journal of Agronomy, 7(2), 132-143. https://doi.org/10.21704/pja.v7i2.2053